started openal work

src/audio/Makefile.am

src/audio/OpenAL/AudioLayer.cpp

src/audio/OpenAL/AudioLayer.hpp

src/audio/OpenAL/AudioManager.hpp

src/audio/OpenAL/AudioManagerImpl.cpp

src/audio/OpenAL/AudioManagerImpl.hpp

src/audio/OpenAL/Context.cpp

src/audio/OpenAL/Context.hpp

src/audio/OpenAL/Device.cpp

src/audio/OpenAL/Device.hpp

src/audio/OpenAL/Makefile.am

src/audio/OpenAL/NullContext.cpp

src/audio/OpenAL/NullContext.hpp

src/audio/OpenAL/NullDevice.cpp

src/audio/OpenAL/NullDevice.hpp

src/audio/OpenAL/NullLayer.cpp

src/audio/OpenAL/NullLayer.hpp

src/audio/OpenAL/NullSource.hpp

src/audio/OpenAL/OpenALDevice.cpp

src/audio/OpenAL/OpenALDevice.hpp